This Small Business Innovation Research (SBIR) Phase 1 project is in the general area of chemical synthesis in the subfield of chemical catalysis. Enzyme catalyzed processes offer significant advantages over traditional chemical methods in organic syntheses, including superior efficiency, stereoselectivity, and specificity. However, soluble and conventionally immobilized enzymes are often inactive under typical laboratory or manufacturing conditions, which may include high temperatures, extremes of pH, near- anhydrous organic solvents, and mixed aqueous-organic solvents. Enzyme crystals, cross-linked using a bifunctional reagent such as glutaraldehyde, constitute a novel form of enzyme immobilization. Such cross-linked enzyme crystals (CLECs) are superior to conventionally immobilized enzymes in many respects. For example, the crystal lattice interactions, supplemented by chemical cross- links, provide the individual enzyme molecules within a CLEC with an enhanced stability that enables CLECs to function in harsh environments (such as elevated temperatures and organic solvents) that would not otherwise be compatible with catalytic activity. These features make CLECs valuable as stereospecific catalytic reagents. In this Phase I study, CLECs of pig liver esterase (PLE) and pig pancreatic lipase (PPL) will be investigated to demonstrate the practical feasibility of CLECs as laboratory catalysis in organic syntheses. Esterase and lipase enzymes were chosen for their superior catalytic characteristics compared with current chemical methods for stereospecific hydrolysis and reduction.
